In a hyper-connected era, a large amount of sensor data is collected from various machines in real-time. There has been a technique used that multi-dimensionally analyzes the data through a preprocess, for example through creation of an OLAP (online analytical processing) cube or the like.
Column-oriented database techniques have also been developed after the MonetDB/X100 execution engine appeared in 2005, thereby necessitating analysis of a large amount of data at a high speed without performing a preprocess.
Data security can be important in storing and analyzing big data in order to conform to various legal regulations and client's needs. In particular, encryption of data is essential for data security.
In various prior art references, transparent data encryption methods that encrypt page units of data files have been carried out for data security. In the prior art, entire pages of data files should be encrypted, and the encrypted entire pages should be decrypted for query and analysis. This requirement for entire page encryption and decryption can lead to performance degradation.
Thus, improved methods, devices, and systems are needed to avoid degradation.